In a typical wheeled vehicle, two wheels at one end (usually the rear end) of the vehicle will be mounted for rolling movement and held against turning while the wheels at the other end (usually the front end) are mounted for rolling and for turning movement. If the vehicle is to be steered to the left or right, the front wheels will be turned in the same direction and the vehicle will move in a curve about a point located generally on a line through the axes of the rear wheels. The further this point is away from the vehicle, the greater the turning radius of the vehicle. For high maneuverability, the vehicle should be capable of having a "zero" turning radius, wherein the vehicle can turn to the left about the left rear wheel or to the right about the right rear wheel.
To avoid scuffing or slipping of the front wheels as the vehicle is turning, the front wheels must rotate unequal amounts during turning. Ideally, each of the front wheels should be perpendicular to the radius line from the center of turning to the center of that front wheel.
In conventional steering mechanisms using lever arms, bell cranks and tie rods or links, turning forces increase as the wheels are turned from center. These steering forces become execessively high as the turning radius approaches zero.
It is an object of the present invention to provide a steering system which will provide a difference in turning of the two steering wheels to prevent excessive tire scuffing, and which will provide a zero turning radius without excessive force being required to turn the steering wheels.